Electric regulation



v ELECTRIC REGULATION Filed March 10, 1930 2 Sheets-Sheet 1 lllll l l llnvenfor':

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July 4, 1933. H. GROB ELECTRIC REGULATION 2 Sheets-$heet 2 Filed March10, 1930 mvmmw- M W BY ATTORNEYS Patented July 4, 1933 HUGO GROB, OFBERLIN, GERMANY ELECTRIC REGULATION Application filed March 10, 1930,Serial No. 434,542, and in Germany March 11, 1929.

This invention relates to regulating appa ratus and more particularly toan apparatus in which the possible range of action of carbon resistancesof the type subjected to pressure '5 may be increased.

One of the objects of this invention is to provide a simple, practical,and inexpensive system and apparatus of the above-mentioned character.Another object is to provide a 19 system and apparatus of theabove-mentioned character that will be of efiicient and thoroughlydependable action and capable of long-continued and lasting action inpractical use. Another object is to provide an apparatus in which avariable resistance may be dependably made to perform its intendedfunction even though the operating characteristic of the load or circuitcontrol by the variable resistance depart from or fall with- J 20 outthe normal range of action of the variable resistance itself.

As conducive to a clearer understanding of certain features of thisinvention, it might at this point he noted that in systems for producingelectric current which, aside from being supplied to a translation orwork circuit such as a lamp circuit, is also to be supplied to anaccumulator or storage battery to charge the latter so that lightingcurrent may be supplied to the lamp circuit when the generator isstationary, the volta e of the dynamo 0:- generator necessary to c largethe battery is too high for the work or lamp circuit; in such systems,there is interposed between the lamps and the generator a selfadjustingresistance, consisting for example of a column or pile of carbon diskssubjected to a variable pressure, and it is in this resistance. throughwhich the current to the lamp circuit flows. that that fraction of thevoltage that is in excess of the lamp voltage is dissipated.

In such systems, since the adjustment or position of the carbon pile isthe same if only a single lamp is burning, the self-adjusting resistancemust naturally be capable'of producing a high ohmic value. In thecase ofa carbon pile, the ratio between the maximum resistance and the lowest.resistance capable of being obtained is limited and the minimum possibleresistance will be relatively hi h; this in many cases is extremelyundesira 1e. One of the dominant aims of this invention is to overcomesuch disadvantages as those just pointed out and to provide a system andapparatus of the above-mentioned nature in which the necessary drop involtage is produced in the carbon maximum resistance of the carbon pilebe relatively low.

Other'objects will be in part obvious or in part pointed outhereinafter.

The invention accordingly consists in the features of construction,combinations of elements, and arrangements of parts, as will beexemplified in the structure to be hereinafter described and the scopeof the application of which will be indicated in the following claims.

In the accompanying drawings in which are shown two of various possibleembodiments of my invention,

Figure 1 shows diagrammatically a system and apparatus embodying myinvention in a preferred form, and

Figure 2 is a similar diagrammatic representation of a possible modifiedform.

Similar reference characters refer to similar parts throughout theseveral views of the drawings.

Referring now first to Figure 1, I have shown a lighting network C whichis to be supplied with current from a storage battery 13 and a dynamo A,the latter serving to charge the battery B. Inasmuch as the volt age ofthe generator A, when the latter is charging the battery B, is too highfor the lamp circuit C. there is provided a carbon pile resistance D,like that above-mentioned which, in the specific embodiment hereillustrated, is connected in front ofthe lamp circuit C when thegenerator is supplying current but is disconnected from in front of thelamp circuit C when the battery B is alone supplying current to thelamps C. To achieve this latter action, I provide an automatic doublepole switch E which may be actuated by suitable means which may includea coil or winding H connected by conductors P and R across the generatorA so that, when pile even though the the dynamo voltage is less than acertain value, such as the battery voltage, the switch E occupies aposition to the right of that shown in Figure l, but when the dynamovoltage exceeds this value, coil H pulls the switch into a position tothe left from that shown in Figure 1.

In the former position (switch E to the right of the position shown inFigure 1) the lamps are supplied with current from the battery B througha circuit which extends from one side of the battery B, conductor 10,switch member 11, switch contact 12, bridging conductor 13, switchcontact 14, switch member 15, conductor 16, winding 17 of a device G tobe more clearly described hereinafter, conductor 18, through the lampnetwork C, conductor 19, and by way of conductor 20 back to the otherside of the battery B.

With the switch E in its left-hand position and hence with the dynamooperating at a suitable voltage, the battery B may receive chargingcurrent over a circuit that extends from one side of the generator A,conductor 21, conductor 22, switch contact 23, switch member 11,conductor 10, battery B, conductor 20, and by way of conductors 24 and25 back to the other side of generator A. The voltage across thegenerator and battery, under these conditions. is too high for the lampsC.

But under these conditions, lamps C are supplied with current from thedynamo A over a circuit which extends from generator A, conductor 21,conductor 26, self adjusting carbon pile resistance D (which may beactuated in any suitable manner), conductor 27, switch contact 28,switch member 15, conductor 16, windings 17 of the device G, conductor18, through the lamp network C, and then by way of conductors 19, 24 and25 to the other side of the generator A. The excess voltage is to bedissipated in the carbon pile D so that the higher generator voltage Ais not applied to the lamps C, but, bearing in mind what has been aboveset forth, the maximum resistance achievable in the carbon pile D is notgreat enough, when the lamp load is very low, as, for example, when onlyone or two lamps are turned on, to cause a suiticiently high IR droptherein to bring about the dissipation of the necessary amount ofgenerator voltage to bring the ultimate lamp voltage down to itsintended value.

Accordingly, I provide an auxiliary resistance F which I arrange to beconnected in parallel with the work circuit C; more specifically.conductor 29 connects one end of resistance Fto one terminal ofgenerator A while a conductor 30 connects the other end to a movablecontact J adapted to coact with a stationary contact K which isconnected by conductor 31 to conductor 27, the latter being in efiect anextension of conductor 18 that leads to one side of the lamp circuit C.

Contact J is mounted upon a member N which is resilient, member N beingin turn carried by an armature M pivotally related to the poles 32 and33 0f the device G and about which poles are the above-describedwindings 17; a spring L opposes swinging movement of the magnet tongueor armature M toward the magnet poles.

The electromagnet G, its armature M, and the spring L are constructed inany suitable manner so that, much as is the case with a voltmeter, thearmature M assumes and retains a different position that varies with themagnitude of excitation of the windings l7. Windings 17 as will be clearfrom what has been above set forth, carry the current flowing to thelamp circuit C and when the lamp load is small, for example when only asingle lamp is burning, armature M is pulled down to such an extent thatcontacts J and K are engaged and resistance F is made effective, beingthereby shunted about the lamp circuit C. Resistance F thus increasesthe load on the generator A but this increased load passes through thevariable carbon pile resistance D in a circuit that will be seen toextend from generator A, conductors 21, 26, carbon pile D, conductor 27,conductor 31, contact K, contact J, conductor 30, resistance F, and byway of c'onductor 29 back to the other side of the generator A.

The resultant current flow through this above-described circuit andhence through the resistance F is of such a magnitude that, togetherwith the current flowing to the lamp circuit, there is produced incarbon pile D the necessary IR drop to bring the lamp voltage C down toits normal or intended value.

If now more lamps are turned, on so that the current to the work circuitC increases, the pull on armature M becomes stronger and armature K isswung to a greater extent in counter-clockwise direction, resilientstrip member N coming in contact with a station* ary stop 0 at a currentvalue through the windings 17 beyond which the above-describedcompensating eilect of resistance F is no longer needed. If the currentto the work circuit C. is further increased, as by turning on morelamps, the continued and now increased pull of armature M moves thelatter in further counter-clockwise direction but this action results inbending the resilient strip N, as shown in the dotted line position, insuch a way that contact member J is lifted from the contact K, thusopening the circuit of resistance F.

Should the work current now diminish, as by turning off some lamps, theabove-described action takes place in reverse order, contacts J and Kbeing closed to bring resistance F and its effect into action again atsuch a value of lamp current where the carbon pile D has to besupplemented by the effect and action of fixed resistance F. If

v Q i becomes zero.

the lamps C are all turned off, windings 17 are deenergized and contactJ is held by spring L out of engagement with fixed contact K.

When the generator is at rest or its voltage insuflicient' to actuateswitch E into its lefthand position, the lamp circuitC is supplied withcurrent directly from the battery in the circuit first above-described,but it will be noted that in this circuit, due to the righthand positionof switch E, neither carbon pile D nor fixed resistance F is madeefi'ective in the illustrative embodiment shown in Figure 1.

I do not wish to be'limited to the specific form of construction for theminimum and maximum switch G as above described and any other suitableswitching mechanism may be employed; as illustrative of a possible otherconstruction for this switching mechanism, I make reference to Figure 2in which the circuit arrangements are the same as above-described andshown with respect to Figure 1, but armature M of the switch G rigidlycarries a contact S adapted to make and retain contact with a stationarycontact T as long as the current flowing through windings 17 is at orbelow the limiting value when fixed resistance F is to be brought intoaction. But in the circuit of resistance F I have included contacts Vand W, one of which, W, for example, is adapted to be engaged by amember X and moved away from contact V, thus to break the circuit ofresistance F when the armature M occupies positions corresponding tothose of Figure 1 when resilient strip N in the latter figure is bent tohold contact J disengaged from contact K.

It will thus be seen that'there has been provided in this invention asystem and apparatus in which the various objects hereinabove pointedout, together with many thoroughly practical advantages, aresuccessfully achieved. It will be seen that even though the maximumresistance of the carbon column D is relatively low and insufficient toproduce the necessary IR drop, at low lamp loads, to protect the lamps Cagainst the higher voltage of the generator A, the carbon resistance isautomatically and in a sense artificially loaded by means of a lowadditional current from the generating plant, thus to bring the IR dropnecessary to pro tect the lamps C against over-voltage; this loading ismaintained as long as the network current is below certain value but isautomatically discontinued immediately that the current to the lampsexceeds this value or It will furthermore be seen that the system andapparatus are well adapted to meet the varying conditions of hardpractical use.

As many possible embodiments may be made of the above invention and asmany changes might be made in the embodiment cuit, switching means forcontrolling the circuit of said auxiliary resistance, and meansresponsive to current flowing to said work circuit adapted, when saidcurrent is below a certain value and the carbon pile resistance isinsutlicient, to close the circuit of said auxiliary resistance and toopen the circuit of the latter when the work circuit current is above acertain value.

2. In apparatus of the character described, in combination, a generator,a storage battery to be charged thereby, a work circuit, apressure-operated carbon pile resistance in circuit with the workcircuit for protecting the latter against over-voltage, a circuitadapted to pass current through said carbon pile to cause an IR droptherethrough, and means responsive to a condition resulting inover-voltage on said work circuit for making said circuit effective.

3. In apparatus of the character described, in combination, a generator,a storage battery to be charged thereby, a work circuit, apressure-operated carbon pile resistance in circuit with the workcircuit for protecting the latter against over-voltage, and means forartificially loading said carbon pile resistance when the resistancethereof is insuflicient to produce the necessary IR drop to protect thework circuit against over voltage.

4. In apparatus of the character described, in combination, a generator,a storage battery to-be charged thereby, a work circuit, apressure-operated carbon pile resistance in circuit with the workcircuit for protecting the latter against over-voltage, an artificialload, a circuit including switching means for supplying current to saidartificial load through said carbon pile, and means operating saidswitching means to make said circuit effective when the load current isbelow a certain value.

5. In apparatus of the character described, in combination, a generator,a storage battery to be chargedthereby, a work circuit, apressure-operated carbon pile resistance in circuit with the workcircuit for protecting the latter against over-voltage, an artificialload, a circuit including switching means for supplyirn current to saidartificial load through said -arbon pile, and electromagnetmeansresponsive to current flowing to said work circuit for controllingsaid switching means.

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6. In apparatus of the character described, in combinatlon, a source ofcurrent, a work circuit supplied thereby, a variable resistance incircuit therewith for protecting the work circuit against over-voltage,means for increasing the IR drop through said resistance, andmeans'responsive to conditions producing excess voltage in said workcircuit for making said last-mentioned means effective.

7. In apparatus. of the character described, in combination, a source ofcurrent, a work circuit supplied thereby, a variable resistance incircuit therewith for protecting the work circuit against over-voltage,means for artificially loading said variable resistance, and meansoperative when the current to said load is below a certain value formaking said last-mentioned means eilective.

8. In apparatus of the character described, in combination, a source ofcurrent, a work circuit, a carbon pile resistance operating by variationin pressure interposed therebetween and having a certain maximumresistance, and means dependent upon conditions when said maximumresistance is insullicient to produce the necessary IR drop to protectsaid work circuit for increasing the IRdrop through the resistance.

9. In apparatus of the character described, in combination, a source ofcurrent, a work circuit, a carbon pile resistance operating by variationin pressure interposed thcrebetween and having a certain maximumresistance, a circuit adapted, when closed, to send additional currentthrough said resistance, and means for closing said circuit operatingwhen the said maximum resistance is insufficient to produce thenecessary IR drop to protect said work circuit.

10. In apparatus of the character described, in combination, a source ofcurrent, a work circuit. a carbon pile resistance operating by variationin pressure interposed therebetween= and having a certain maximumresistance, an artificial load connected in a circuit so that thecurrent supplied thereto passes through said resistance. switching meansfor controlling the circuit of said artificial load. and meansresponsive to a function of the current supplied to said work circuitfor operating said switching means.

11. In apparatus of the character described, in combination, a source ofcurrent, a work circuit, a carbon pile resistance operating by variationin pressure interposed therebetween and having a certain maximumresistance, an artificial load connected in a circuit so that thecurrent supplied thereto passes through said resistance, switching meansfor controlling the circuit of said artificial load, and means operatingwhen said maximum resistance is insufficient to cause the necessary IRdrop to protect said work circuit for operat ing said switching means tomake said artificial load circuit effective.

12. In apparatus of the character described, in combination, a source ofcurrent, a work circuit, a carbon pile resistance operating by variationin pressure interposed therebetween and having a certain maximumresistance, means for artificially loading said resistance and includingswitching means adapted in one position to effect artificial loading ofsaid resistance and in another position to discontinue artificialloading thereof, and operating means for said switching means includingmeans for holding the latter in said first position when the current tosaid work circuit is below a certain value and for holding it in saidsecond position when the current to the work circuit is above saidValue.

13. In apparatus of the character described, in combination, a source ofcurrent, a work circuit supplied thereby, an artificial load adapted tobe connected in parallel with said work circuit, and means responsive tothe establishing of current in said work circuit for connecting saidartificial load in parallel with said work circuit and upon increases ofsaid current to a predetermined value for disconnecting said load fromsaid'work circuit.

14. In apparatus of the character described, in combination, a source ofcurrent, a work circuit supplied thereby, a load adapted to be connectedto said source, and means responsive to establishing said work circuitfor connecting said load to said source and responsive to the increaseddemand of said work circuit for disconnecting said load from saidsource.

15. In apparatus of the character described, in combination, a source ofcurrent, a work circuit supplied thereby, means including a carbon pileresistance for controlling a function of said source interposed betweensaid source and said work circuit. and means responsive to a smallcurrent demand of said work circuit for increasing the potential dropacross said carbon pile and responsive to an increased current demand ofsaid work circuit for decreasing the potential drop across said carbonpile.

In testimony whereof I have. affixed my signature.

HUGO GROB.

